The water in the Outdoor StreamLab is easy to get into and study, as Katie Kramarczuk, seen here with a flow meter, shows.

Field of streams

New Outdoor StreamLab opens a water world to researchers

By Deane Morrison

September 17, 2008

The "father of waters" has a new offspring at the University of
Minnesota's St. Anthony Falls Laboratory (SAFL), and the public is
invited to see it. Researchers have diverted Mississippi River
water to create a meandering stream on a grassy riverbank next to
SAFL opposite downtown Minneapolis. The baby brook in the new
Outdoor StreamLab is open to both the elements and experimental
control, making it an ideal facility for studying such topics as
the ecological roles of streams, flood control, and stream
restoration. The Outdoor StreamLab will hold a free public open
house from 3 to 5 p.m. this Friday (September 19) as part of its
grand opening. The lab is at 2
Third Ave. S.E., Minneapolis. A project of SAFL and the National Center for Earth-surface
Dynamics, the Outdoor StreamLab is only a few months old but is
already attracting two important demographic groups: top-notch
researchers and populations of algae, insects, and other life.
Among its denizens are a pair of mallards that seem to have adopted
the stream as a vacation home and can often go paddling up the
channel, oblivious to people.

The ducks add a touch of levity, but the need to understand streams
is serious. Factors such as floods, drainage patterns altered by
development, and heavy loads of chemicals and sediment are changing
the world's waterways; dealing with all this has to be done right,
and that requires research on realistic riverine systems. That need
is illustrated by what happened at Uvas Creek, Calif., says Anne
Lightbody, a research associate at SAFL and manager of the Outdoor
StreamLab.

"Twenty years ago, the people bringing this
issue up and who wanted developments changed to accommodate storm
water management were considered mavericks. Now it's standard."

"They tried to turn it from a braided stream [with an intricate
pattern of channels coursing through sand] to a [simpler]
meandering one," she explains. "The next spring, it flooded and
reverted. People didn't take 'what the river wanted to do' into
account." Trout streams are another example of how understanding
ecological relationships is vital to preserving things we value.
"Trout streams must be cold," says Lightbody. If trees along the
banks are cut, there goes the shade, and the water starts to warm
up. Also, changing patterns of land use may reduce the amount of
groundwater entering a stream. Groundwater, with its typically cold
and steady flow, not only cools streams directly but helps keeps
their water levels from dropping. This minimizes shallow spots,
which are prone to warming by the sun. One of the projects under
way at the lab is an investigation of how loads of sediment affect
invertebrates, fish, and the physical stream structure. Another
examines how vegetation affects the flow of streams and the
retention of flood water. "We need to understand what the flood
plains are doing and what ecosystem services they provide," says
Lightbody. For example, if flood plains retain water long enough,
they may absorb dissolved pollutants and sediments before the water
seeps back into the river channel. But the ability to keep streams
healthy rests on more than science; human acceptance is also
crucial. Lightbody is part of an upcoming study to look at the
tradeoffs between public acceptance of ecosystems like wetlands and
the services, such as cleansing waters of nutrients, that
ecosystems perform. Even a very small change in a project can
increase acceptance, says Lightbody. For example, a wetland may be
seen as unsightly--until it acquires a mowed path around it and
benches for birdwatching. But mowing has its downside. "With
streams and lakes, people want to mow right down to the water,"
Lightbody says. "How do you convince people that a buffer is OK?
Can we put in paths or something to make it acceptable?" Attitudes
do change, though. Today, Lightbody says, storm water retention
ponds go into every new development and are required by every
zoning regulation she knows about. But it was not always so.
"Twenty years ago, the people bringing this issue up and who wanted
developments changed to accommodate storm water management were
considered mavericks," she explains. "Now it's standard.
"Understanding how rivers work can help us make smart decisions
about how and where and whether to develop." Plans call for adding
a second, longer stream to the lab.